Service Location Protocol (SRVLOC)

The Service Location Protocol provides a scalable framework for the discovery and selection of network services. Using this protocol, computers using the Internet need little or no static configuration of network services for network based applications. This is especially important as computers become more portable, and users less tolerant or able to fulfill the demands of network system administration.


XXX - add a brief description of SRVLOC history

Protocol dependencies

  • UDP: Typically, SRVLOC uses UDP as its transport protocol. The well known TCP/UDP port for SRVLOC traffic is 427.

Example traffic

Service Location Protocol
    Version: 2
    Function: DA Advertisement (8)
    Packet Length: 81
   +Flags: 0x0000
    Next Extension Offset: 0
    XID: 0
    Lang Tag Len: 2
    Lang Tag: en
    Error Code: No Error (0)
    DAADVERT Timestamp: Aug 24, 2007 11:20:58.000000000
    URL Length: 39
    URL: service:directory-agent://
    Scope List Length: 11
    Scope List: OUR-DEFAULT
    Attribute List Length: 0
    Attribute List:
    SLP SPI Length: 0
    SLP SPI:
    Auths: 0 


The SRVLOC dissector is fully functional. See discussion below…

Preference Settings

(XXX add links to preference settings affecting how SRVLOC is dissected).

Example capture file

XXX - Add a simple example capture file to the SampleCaptures page and link from here. Keep it short, it's also a good idea to gzip it to make it even smaller, as Wireshark can open gzipped files automatically.

Display Filter

A complete list of SRVLOC display filter fields can be found in the display filter reference

Show only the SRVLOC based traffic:


Capture Filter

You cannot directly filter SRVLOC protocols while capturing. However, if you know the UDP port used (see above), you can filter on that one.

External links


The attribute-list display is written to display only attributes of one type (unknown). Others are either not displayed or displayed incorrectly. –BillFlorac

Imported from on 2020-08-11 23:25:49 UTC